function Snake(el){
    this.el=el
    this.len=20


    this.snakeObj=[
        {x:3,y:2,color:'red',el:null},
        {x:2,y:2,color:'blue',el:null},
        {x:1,y:2,color:'blue',el:null}
    ]
    this.direction='right'
}
Snake.prototype.remove=function(){
    for (let i = 0; i<this.snakeObj.length; i++) 
    {
        if (this.snakeObj[i].el)
        {
            this.el.removeChild(this.snakeObj[i].el)
        }
    }
    
}
Snake.prototype.create=function(){
        this.remove()
    for(let i=0;i<this.snakeObj.length;i++){
        let divObj=document.createElement('div')
        divObj.style.width=this.len+'px'
        divObj.style.height=this.len+'px'
        divObj.style.position='absolute'
        divObj.style.left=this.snakeObj[i].x*this.len+'px'
        divObj.style.top=this.snakeObj[i].y*this.len+'px'
        divObj.style.background=this.snakeObj[i].color
        this.snakeObj[i].el=divObj
        this.el.appendChild(divObj)
    }
}
Snake.prototype.move=function(){
    for (let i = this.snakeObj.length - 1; i>0; i--) {
       
        this.snakeObj[i].x = this.snakeObj[i-1].x
        this.snakeObj[i].y = this.snakeObj[i-1].y
    }

    switch (this.direction) {
        case 'top':
            this.snakeObj[0].y -= 1
            break;
        case 'bottom':
            this.snakeObj[0].y += 1
            break;
        case 'left':
            this.snakeObj[0].x -= 1
            break;
        case 'right':
            this.snakeObj[0].x += 1
            break;
    }
    this.create()
}